Augeas - a configuration API

Augeas is a configuration editing tool. It parses configuration files in
their native formats and transforms them into a tree. Configuration changes
are made by manipulating this tree and saving it back into native config
files.

Augeas is:

An API provided by a C library

A command line tool to manipulate configuration from the shell (and shell
scripts)

Language bindings to do the same from your favorite scripting language

Canonical tree representations of common configuration files

A domain-specific language to describe configuration file formats

Augeas goals:

Manipulate configuration files safely, safer than the ad-hoc techniques
generally used with grep, sed, awk and similar mechanisms in scripting
languages